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991.
Abrari Saeid Daneshvari-Esfahlan Vahid Hosseini Mir Ghasem Mahmoodi Raana Hacker Viktor 《Journal of Applied Electrochemistry》2022,52(4):755-764
Journal of Applied Electrochemistry - In the present work, Ni@Pd core–shell nanoparticles are successfully deposited on multi-walled carbon nanotubes as support and investigated their... 相似文献
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994.
Jianfei Huang Jaewon Lee Joachim Vollbrecht Viktor V. Brus Alana L. Dixon David Xi Cao Ziyue Zhu Zhifang Du Hengbin Wang Kilwon Cho Guillermo C. Bazan Thuc-Quyen Nguyen 《Advanced materials (Deerfield Beach, Fla.)》2020,32(1):1906027
Sensitive detection of near-infrared (NIR) light enables many important applications in both research and industry. Current organic photodetectors suffer from low NIR sensitivity typically due to early absorption cutoff, low responsivity, and/or large dark/noise current under bias. Herein, organic photodetectors based on a novel ultranarrow-bandgap nonfullerene acceptor, CO1-4Cl, are presented, showcasing a remarkable responsivity over 0.5 A W−1 in the NIR spectral region (920–960 nm), which is the highest among organic photodiodes. By effectively delaying the onset of the space charge limited current and suppressing the shunt leakage current, the optimized devices show a large specific detectivity around 1012 Jones for NIR spectral region up to 1010 nm, close to that of a commercial Si photodiode. The presented photodetectors can also be integrated in photoplethysmography for real-time heart-rate monitoring, suggesting its potential for practical applications. 相似文献
995.
Cover Picture: En Route to New Therapeutic Options for Iron Overload Diseases: Matriptase‐2 as a Target for Kunitz‐Type Inhibitors (ChemBioChem 7/2016) 下载免费PDF全文
996.
Dániel Horváth Nóra Taricska Prof. Dr. Ernő Keszei Dr. Pál Stráner Dr. Viktor Farkas Prof. Dr. Gábor K. Tóth Prof. Dr. András Perczel 《Chembiochem : a European journal of chemical biology》2020,21(5):681-695
A new approach to monitor disulfide-bond reduction in the vicinity of aromatic cluster(s) has been derived by using the near-UV range (λ=266–293 nm) of electronic circular dichroism (ECD) spectra. By combining the results from NMR and ECD spectroscopy, the 3D fold characteristics and associated reduction rate constants (k) of E19_SS, which is a highly thermostable, disulfide-bond reinforced 39-amino acid long exenatide mimetic, and its N-terminally truncated derivatives have been determined under different experimental conditions. Single disulfide bond reduction of the E19_SS model (with an 18-fold excess of tris(2-carboxyethyl)phosphine, pH 7, 37 °C) takes hours, which is 20–30 times longer than that expected, and thus, would not reach completion by applying commonly used reduction protocols. It is found that structural, steric, and electrostatic factors influence the reduction rate, resulting in orders of magnitude differences in reduction half-lives (900>t1/2>1 min) even for structurally similar, well-folded derivatives of a small model protein. 相似文献
997.
Galina E. Yakovleva Anatoly I. Romanenko Alexandra Yu. Ledneva Viktor A. Belyavin Vitalii A. Kuznetsov Alexandr S. Berdinsky Alexandr T. Burkov Petr P. Konstantinov Sergey V. Novikov Mi-Kyung Han Sung-Jin Kim Vladimir E. Fedorov 《Journal of the American Ceramic Society》2019,102(10):6060-6067
We investigate the thermoelectric properties of bulk polycrystalline samples of WSe2-based compounds with partial substitutions in the cationic (W) and the anionic (Se) sublattices in the temperature range from 4.2 to 650 K. The substitution of W for Nb leads to a significant increase in the charge carrier concentration, however, deteriorates the charge carrier mobility. In contrast, the substitution of selenium for sulfur increases the charge carrier mobility, the thermal conductivity, and the Seebeck coefficient but conductivity changes non-monotonical. We show that the addition of sulfur in anionic sublattice affects the grain sizes in the polycrystalline material. Using substitutions in the anionic and cationic sublattices, we find the optimal ratio of the elements for better thermoelectric efficiency. The W0.98Nb0.02Se1.7S0.3 sample showed the best value of the figure of merit ZT = 0.26 (T = 650 K). 相似文献
998.
Fomin E. V. Bondarev A. D. Rumyantseva A. I. Maurer T. Pikhtin N. A. Tarasov S. A. 《Technical Physics Letters》2019,45(3):221-224
Technical Physics Letters - A study of the surface topography and optical characteristics of thin AlN films used as passivating and antireflection coatings deposited on n-GaAs (100) substrates by... 相似文献
999.
Oleg Lupan Niklas Wolff Vasile Postica Tudor Braniste Ingo Paulowicz Viktor Hrkac Yogendra Kumar Mishra Ion Tiginyanu Lorenz Kienle Rainer Adelung 《Ceramics International》2018,44(5):4859-4867
Tin oxide nanowires (SnO2 NWs) exhibit large potential for applications in sensor and detector technology. Using a flame transport synthesis method, high-quality single crystalline SnO2 nanowires (NWs) with Zn2SnO4 dots functionalized surface were synthesized on a large scale. The individual SnO2:Zn2SnO4 nanowire based ultraviolet photodetector and ethanol vapors nanosensors were fabricated by contacting an individual nanowire to pre-patterned Au electrodes via a FIB/SEM system. The photodetector structure exhibited excellent photoconductive performance in terms of high response to the 375 nm ultraviolet light irradiation, ultra-fast response and recovery time at different temperatures (25–300 K). It also showed a long term stability and reliability. The n-type semiconducting behavior of the SnO2:Zn2SnO4, forms an excellent material for fabricating highly sensitive and rapid responding sensors, which will enable the development of high-performance multi-functional devices. 相似文献
1000.
Dynamic adaptation of online ensembles for drifting data streams 总被引:1,自引:0,他引:1
M. Kehinde Olorunnimbe Herna L. Viktor Eric Paquet 《Journal of Intelligent Information Systems》2018,50(2):291-313
The success of data stream mining techniques has allowed decision makers to analyze their data in multiple domains, ranging from monitoring network intrusion to financial markets analysis and online sales transactions exploration. Specifically, online ensembles that construct accurate models against drifting data streams have been developed. Recently, there has been a surge in interest in mobile (or so-called pocket) data stream mining, aiming to construct near real-time models for data stream mining applications that run on mobile devices. In such a setting, it follows that the computational resources are limited and that there is a need to adapt analytics to map the resource usage requirements. Consequently, the resultant models should not only be highly accurate, but they should also adapt swiftly to changes. In addition, the data mining techniques should be fast, scalable, and efficient in terms of resource allocation. It then becomes important to consider Return on Investment (ROI) issues such as storage requirements and memory utilization. This paper introduces the Adaptive Ensemble Size (AES) algorithm, an extension of the Online Bagging method, to address these issues. Our AES method dynamically adapts the sizes of ensembles, based on ROI usage patterns. We illustrate our approach by analyzing the performances against both synthetic and real-world data streams. The results, when comparing our AES algorithm with the state-of-the-art, indicate that we are able to obtain a high Return on Investment (ROI) and to swiftly adapt to change, without compromising on the predictive accuracy. 相似文献